Psychological well-being within eating disorder patientsessay.utwente.nl/74827/1/Fenne van Holthe_MA_BMS.pdfPsychological well-being within eating disorder patients Validation of the

Psychological well-being within eating disorder patients

Validation of the Dutch scales of psychological well-being and relations with maladaptive

personality functioning

Master of Science thesis, 10 april 2018

Fenne E.C. van Holthe

University of Twente

Faculty of Behavioural, Management and Social Sciences

Programme: Positive Psychology and Technology

P.M. ten Klooster, PhD, 1st supervisor

J.A. de Vos, MSc, 2nd supervisor

Abstract

Although psychological well-being (PWB) has been found to be substantially impaired within

eating disorder patients, the Dutch scales of PWB have not been psychometrically tested in a

clinical population yet. The theoretical concept of PWB includes six dimensions: Purpose in

Life, Personal Growth, Autonomy, Environmental Mastery, Self-Acceptance, and Positive

Relationships with Others. The aim of this study was to examine the factorial validity, internal

consistency, convergent validity, and incremental validity of the PWB scales. In addition,

relations between PWB and maladaptive personality functioning were explored.

The sample consisted of 502 patients seeking treatment at a specialized center for eating

disorders. Cross-sectional data from the intake were used to test the psychometric properties of

the 8/9-item per scale version. The factor structure was explored through principal component

analyses with oblimin rotation, internal consistencies were obtained through Cronbach’s alpha

analyses, and incremental validity was tested through multivariate linear regression analyses.

Convergent validity and correlations with maladaptive personality functioning were examined

through bivariate correlation tests.

About two-third of the items loaded on the expected six dimensions of PWB indicating

partial support of the 6-factor structure. Internal consistencies of the scales were fair to good.

Correlations with other measures were significant and mostly in accordance with expectations.

PWB dimensions explained 3.1% additional variance in eating pathology above and beyond

psychopathological symptoms, specifically Autonomy and Self-Acceptance. Beyond this,

multiple significant correlations were found between PWB dimensions and domains of

maladaptive personality functioning.

The construct of PWB can be measured in a fairly reliable and valid way through the

Dutch PWB scales. A confirmative factor analysis is recommended to test the factor structure

more extensively and to examine the instrument’s invariance between groups to interpret group

differences. For the purpose of routine outcome monitoring, further research is also

recommended on test-retest reliability and the scales’ capabilities to measure changes over time.

Present findings supported incremental validity, but additional support may be obtained from a

longitudinal study. The relationship between PWB and maladaptive personality functioning

needs to examined into more depth considering the possible implications for the treatment of

patients with comorbid personality disorders.

Table of contents

Introduction ............................................................................................................................4

Method ...................................................................................................................................9

Results.................................................................................................................................. 14

Discussion ............................................................................................................................ 22

References ............................................................................................................................ 29

Appendix A: PWB-items of the PGGS ................................................................................. 34

Appendix B: Supplementary results ...................................................................................... 36

PWB within eating disorder patients | 4

Introduction

It is only recently that psychological well-being (PWB) has become a research focus in the

study and treatment of eating disorder patients (De Vos, LaMarre, Radstaak, Bijkerk,

Bohlmeijer, & Westerhof, 2017; Tomba, Offidani, Tecuta, Schumann, & Ballardini, 2014;

Tomba, Tecuta, Schumann, & Ballardini, 2017). Although the World Health Organization

(1948) has stressed the positive dimension of mental health since decades, most research

exclusively focussed on psychopathological dysfunction. Only at the beginning of this century,

positive mental health in eating disorders was addressed in terms of quality of life and

subjective well-being (Jenkins, Hoste, Meyer, & Blissett, 2011).

A more comprehensive approach to well-being, however, addresses the degree to which

a person is fully functioning (Ryan & Deci, 2001). Besides the tendency to focus on happiness

in terms of pleasure attainment and pain avoidance (hedonia), people are driven to fulfill their

talents and potentialities (eudemonia). In other words, life is not merely about having a pleasant

life but also about having a good life encompassing meaning and self-realization. The

theoretical conceptualization of PWB (i.e. positive psychological functioning) was pioneered

and developed by Ryff (1989, 1995) and generated from multiple frameworks. Included in the

model are six core dimensions: the belief that life has a purpose and meaning (Purpose in Life),

a sense of growth and development (Personal Growth), a sense of self-determination

(Autonomy), the capacity to manage one’s life effectively (Environmental Mastery), positive

self-evaluation (Self-Acceptance) and the holding of warm and qualitative relationships with

other people (Positive Relationships with Others). The operationalization of each dimension is

shown in Table 1.

The relation between PWB and mental illness has been addressed in several studies. For

example, multiple indicators of depression (i.e. dysfunctional energy and dysfunctional affect)

showed negative associations with all dimensions of PWB, in particular with Self-Acceptance

and Environmental Mastery (Ryff & Keyes, 1995). Also, symptoms in patients suffering from

a panic disorder showed negative associations with Environmental Mastery, Personal Growth,

Purpose in Life and Self-Acceptance (Fava, Rafanelli, Ottolini, Ruini, Cazzaro, & Grandi,

2001). Although positive psychological functioning is related to mental illness, the ‘two-

continua model of mental health’ states that this relation is not perfect (Keyes, 2005).

Experiencing many psychopathological symptoms may increase the chance of decreased

positive functioning, but this is not necessarily always the case. An individual suffering from a

mental illness may still have a high degree of PWB at the same time and vice versa. In other


words, a lack of psychopathological symptoms does not imply optimal functioning (Lamers,

Westerhof, Bohlmeijer, Ten Klooster, & Keyes, 2011). The complementary role of positive

functioning to mental illness points out the need of assessing PWB in addition to

psychopathological symptoms in patients suffering from a mental disorder.

Table 1

Dimensions of psychological well-being

Purpose in Life

Has plans and goals in life and a sense of directedness. Feels there is a meaning to present and

past life and holds beliefs that give life a certain purpose.

Personal Growth

Has a feeling of continued development and the perception of oneself as growing and

developing. Has an open attitude towards new experiences and a sense of realization of

potentialities.

Autonomy

Is self-determined and independent. Resists social pressure to think or act in a certain manner

and regulates behaviour from within. Also, uses personal standards for self-evaluation.

Environmental Mastery

Has a sense of mastery and competence in managing environmental demands and controlling

complex activities. Uses effectively surrounding opportunities and chooses and creates

contexts which suit personal needs and values.

Self-Acceptance

Has a positive attitude towards oneself and the acknowledgement of multiple aspects of the

self including positive and negative characteristics. Has a positive feeling on the past and

course of life.

Positive Relationships with Others

Has warm, trustful relationships with others and is involved in the well-being of others. Has

capabilities like empathy, affection and intimacy as well as an understanding of the concept of

give and take of human relationships.

Suffering from an eating disorder has a profound impact on patients’ lives, as research

revealed that people with eating disorders have the lowest levels of quality of life of all

psychiatric illnesses (Jenkins et al., 2011). With increasing prevalence rates and a peak age of

onset between 14-19 years, eating disorders are among the most prevalent disorders in

adolescence and often take a chronic course (Herpertz-Dahlmann, 2015). Most eating disorders

are characterized by disturbed eating or eating-related behaviour and weight changes which

very often involves continuous preoccupation with eating and weight-control practices. The

main types of eating disorders include anorexia nervosa (AN), bulimia nervosa (BN) and binge-

eating disorder (BED) (DSM-5; APA, 2013). Although eating-related behaviour differs

between AN and BN, self-evaluation in both types is highly influenced by the overevaluation


of and dissatisfaction with one’s body weight and shape. As a result, patients with AN

persistently restrict energy intake leading to significant low body weight (DSM-5; APA, 2013).

The severe and prolonged starvation, particularly present in AN-patients, can seriously

influence the brain and bone development (Herpertz-Dahlmann, 2015). Of all mental illnesses,

AN has the highest mortality rate (Hoek, 2006). BN-patients experience recurrent episodes of

binge eating (i.e. uncontrolled overeating) followed by inappropriate compensatory behaviour

such as self-induced vomiting or misuse of laxatives. Although BED-patients also display

severe and uncontrolled overeating behaviour in recurrent episodes, they do not engage in

inappropriate compensatory behaviours like BN-patients (DSM-5; APA, 2013). Lifetime

prevalences for AN and BN within a Dutch nationally representative survey (NEMESIS-2)

were respectively 2.0% and 1.1% among women, and 0.0% and 0.2% among men (Bijl, Ravelli,

& Van Zessen, 1998). In the US, a nationwide representative survey demonstrated lifetime

prevalence rates for AN, BN and BED of 0.9%, 1.5%, and 3.5% among women, and 0.3%,

0.5%, and 2.0% among men (Hudson, Hiripi, Pope, & Kessler, 2007). The age of onset in BED-

patients tended to be later (around the age of 25) than those in AN- and BN-patients.

Additionally, comorbidity with other disorders such as mood, anxiety, impulse-control, and

substance use disorders was found to be common. Also, meta-analysis showed frequent

comorbidity with personality disorders (Martinussen et al., 2017).

The role of PWB within eating disorders was first investigated by Tomba et al. (2014).

Through a controlled study, involving a sample of 245 outpatients covering the main eating

disorders, they found that PWB was substantially impaired. Compared to healthy controls,

patients with eating disorders showed lower scores on Autonomy, Environmental Mastery,

Positive Relationships with Others, and Self-Acceptance. The findings also showed differences

between diagnostic groups. For example, BN-patients reported lower scores on all dimensions

than healthy controls whereas BED-patients only scored lower on Autonomy, Environmental

Mastery, and Self-Acceptance. AN-patients showed impaired PWB regarding Positive

Relationships with Others and Self-Acceptance, but similar scores to healthy controls on the

other dimensions of PWB (Tomba et al., 2014).

The additional value of positive functioning is reflected by previous findings showing

that positive scores on PWB protect against future psychopathological symptoms in general and

contribute to relapse prevention (Lamers, Westerhof, Glas, & Bohlmeijer, 2015; Schotanus-

Dijkstra, Ten Have, Lamers, De Graaf, & Bohlmeijer, 2016). In an exploratory study on

outpatients with eating disorders it was found that, in addition to standard measurement of BMI,

symptomatology and behavioural parameters, treatment outcome in eating disorders may


benefit from changes in positive functioning such as PWB. In particular, the enhancement of

warm relationships and self-acceptance may strengthen treatment outcome (Tomba et al.,

2017). Moreover, a systematic review and qualitative meta-analysis by De Vos et al. (2017)

showed that former eating disorder patients rate PWB as a key criterion for recovery in addition

to symptom remission. Self-Acceptance, Positive Relationships with Others, Personal Growth

and Autonomy were the most frequently mentioned dimensions of PWB. Given these findings,

it was recommended by the researchers to include measurements of PWB in future outcome

studies and in routine outcome measurement in addition to measuring pathology change or

remission.

The theoretical construct of PWB was operationalized into the Scales of Psychological

Well-Being (SPWB; Ryff, 1989). Initially, this self-report assessment instrument consisted of

32-items per dimension. Examined in a general population sample of 321 young, middle-aged

and older adults, items that showed low correlations with their own scale were deleted. This

resulted into an instrument with 20 items per scale with high internal consistency coefficients

for all six subscales. Besides reliability, preliminary evidence for construct validity was

provided. Correlations with other measures of positive functioning (i.e. life satisfaction, affect

balance, self-esteem, internal control, and morale) were weakly to strongly positive and

correlations with other measures of negative functioning (i.e. powerful others, chance control,

depression) were weakly to moderately negative. Although correlations between some of the

PWB scales were found to be rather strong (Self-Acceptance correlated strongly with

Environmental Mastery and Self-Acceptance correlated strongly with Purpose in Life), initial

evidence supported the view that different underlying constructs were involved. This was

illustrated by the facts that items of each scale correlated most strongly with their own scale,

the scales had differential patterns of associations with other measures, and items loaded on

different factors of well-being. This pilot-study resulted into different versions ranging from

14-items per scale to 3-items per scale. Following this, the psychometric properties were tested

in a nationwide sample using the 3-item per scale version. Internal consistencies of the scales

were found to be low to modest this time, but confirmatory factor analyses supported the 6-

factor model (Ryff & Keyes, 1995). A few years later, the 6-factor structure was confirmed for

the same short version in another large sample (Clarke, Marshall, Ryff, & Wheaton, 2001).

Although the SPWB is a popular measure in practice, it is controversial in the literature. Not all

analyses supported a 6-factor structure or even multidimensionality, especially when using a

longer version (Kafka & Kozma, 2002; Springer & Hauser, 2006; Triadó, Villar, Solé, &

Celdrán, 2007; Van Dierendonck, 2004). Van Dierendonck (2004) examined the psychometric


properties of different versions (3-items, 9-items and 14-items per scale) in two Dutch samples

consisting of students (N=233) and professionals (N=420). Whereas factorial validity was only

supported by the 3-items per scale version, internal consistencies were not acceptable. On the

other hand, good reliabilities were found for the longer 14-items per scale version, but findings

did not support factorial validity. The length of the scales was therefore constrained to 6-8 items

per scale which showed the best overall psychometric quality (Van Dierendonck, 2004).

Until now, psychometric testing of the PWB scales has been almost completely limited

to non-clinical populations. Psychometric assessment of the Dutch PWB scales in a clinical

population, in particular within eating disorder patients, has not been conducted so far.

Although former patients indicated that PWB plays an important role in recovery, the

incremental value of PWB in explaining pathological symptoms has not been explored either.

Furthermore, little is known about the relation between PWB and personality

functioning. Comorbid personality disorders are common in patients with eating disorders and

previous findings suggested that they worsen the long-term outcome (Martinussen et al., 2017).

Hence, it may help to consider associations between personality functioning and PWB in order

to better understand the etiology of eating disorders and to maintain and develop effective

treatments (Farstad, McGeown, & Von Ranson, 2016). The dimensional personality disorders

model conceptually differentiates impaired personality functioning from the presence of

pathological traits (section III, DSM-5; APA, 2013). A strong association between the two was

found, but they also showed incremental validity above each other in predicting personality

disorders (Bastiaansen, De Fruyt, Rossi, Schotte, & Hofmans, 2013; Berghuis, Kamphuis, &

Verheul, 2012). The generic and changeable components of maladaptive personality

functioning, thus assumed to be present in all personality disorders, include Self-Control,

Identity Integration, Responsibility, Relational Capacities and Social Concordance (Verheul et

al., 2008). Although previous studies suggested that aspects of PWB are linked to identity status

(Helson & Srivastava, 2001), self-enhancing cognitions (Taylor, Lerner, Sherman, Sage, &

McDowell, 2003a, b), emotion regulation (Gross & John, 2003), general personality traits

(Lopes, Salovey, & Straus, 2003; Schmutte & Ryff, 1997), coping strategies (Kling, Seltzer, &

Ryff, 1997), and social comparison processes (Heidrich & Ryff, 1993; Kwan, Love, Ryff, &

Essex, 2003), so far knowledge on possible associations between PWB and maladaptive

personality functioning is limited. The establishment of a relation between these two, however,

may give some indication for the treatment of eating disorder patients with a comorbid

personality disorder.


Following all this, the aim of this study was to evaluate the psychometric properties of

the PWB scales within a Dutch clinical population of eating disorder patients. Specifically, the

factorial validity, internal consistency, convergent validity, and incremental validity were

examined. In addition, possible associations between the dimensions of PWB and the

dimensions of maladaptive personality functioning were explored.

Method

Participants and procedure

Participants were Dutch patients seeking treatment for an eating disorder and meeting the

diagnostic criteria as such (DSM-5; APA, 2013). Only patients aged 16 years and older, with a

referral from the general practitioner, were included. Somatic instability was an exclusion

criterium. Comorbidity was common within participants (i.e. mood and personality disorders),

but only in the case of a second diagnosis. All participants gave their informed consent to

anonymously use their data for research purposes. Ethical approval was obtained from the

Ethics Committee of the Faculty of Behavioural, Management and Social Sciences of the

University of Twente.

Data were collected through routine outcome monitoring by the Human Concern

Foundation, a specialized treatment center for eating disorders in The Netherlands. The cross-

sectional data from intake (i.e. prior to treatment) were collected between January 2016 and

August 2017. At the time of registration, participants first provided some demographic

information followed by a screening of pathological symptoms. Patients were then invited for

an intake day, consisting of several interviews with different therapists (e.g. dietician,

experience professional, psychiatrist). Based on all information, patients were diagnosed by the

psychiatrist according to the criteria of the DSM-5 (APA, 2013). In addition, participants filled

out several self-report questionnaires, mostly online.

Measures

The Dutch self-report questionnaire Positieve Geestelijke Gezondheidsschaal (PGGS; Van

Dierendonck, 2011) measures PWB and spiritual well-being. It comprises 66 items and uses a

6-point Likert scale ranging from 1 (strongly disagree) to 6 (strongly agree). For the purpose

of this study, only the six original PWB scales were used (Ryff, 1989). These scales contained

52 translated items (Appendix A). Purpose in Life (‘I sometimes feel as if I have done all there

is to do in life’), Personal Growth (‘I am not interested in activities that will expand by


horizons’), Self-Acceptance (‘In general, I feel confident and positive about myself’), and

Positive Relationships with Others (‘Most people see me as loving and affectionate’) are

measured by 9 items each. Autonomy (‘I tend to worry about what other people think of me’)

and Environmental Mastery (‘In general, I feel I am in charge of the situation in which I live’)

are both measured by 8 items each. Higher scores on the subscales reflect higher well-being.

Previous studies have shown conflicting results on the factor structure of the PWB scales. A 6-

factor structure was found by Ryff (1989) for the 3-item per scale version whereas a Spanish

study found a 15-factor structure for the 9-item per scale version (Triadó et al., 2007). Good

internal consistencies were found for the 8/9 items per scale version, ranging from 0.73 to 0.83.

Only for the Personal Growth scale, reliability was found to be low (α = 0.65) (Van

Dierendonck, 2004). The psychometric properties of the PWB scales in this study will be

described in the Results section.

The Dutch version of the Mental Health Continuum-Short Form (MHC-SF; Keyes et al., 2008;

Dutch version: Lamers et al., 2011) was developed to assess positive mental health and

comprises 14 items on emotional, psychological, and social well-being. All items measure the

frequency of a feeling in the past month on a 6-point Likert scale (never, once or twice a month,

about once a week, two or three times a week, almost every day, every day). Higher scores

reflect higher well-being. The emotional well-being subscale comprises three items (‘How often

did you feel satisfied’), the social well-being subscale five items (‘How often did you feel that

people are basically good‘) and the psychological well-being subscale six items (‘How often

did you feel that you liked most parts of your personality‘). Good psychometric properties were

found for the MHC-SF, with good internal reliability for the total scale as well as the emotional

and psychological well-being scale. Internal consistency of the social well-being scale was

found to be fair (Lamers et al., 2011). In this study, internal consistency of the total scale was

excellent (α=0.90). Like previous findings, the subscales emotional well-being and

psychological well-being showed good internal consistencies (respectively 0.86 and 0.83)

whereas internal consistency of the social well-being subscale was fair (α=0.72).

The Dutch version of the Outcome Questionnaire-45 (OQ-45; De Jong, Nugter, Lambert, &

Burlingame, 2009) is a 45-item instrument for screening psychopathological symptoms, often

being used to monitor treatment response. Respondents rate the frequency of symptoms in the

past week on a 5-point Likert scale ranging from 0 (never) to 4 (almost always), i.e. higher

scores reflect more pathological symptoms. Symptom Distress (including depression and


anxiety, e.g. ‘I feel nervous’) comprises 25 items, Interpersonal Relationships (loneliness,

conflict with others and marriage and family difficulties, e.g. ‘I feel irritated‘) comprises 11

items, and Social Role (difficulties in the workplace, school or home duties, e.g. ‘I work/study

too much‘) comprises 9 items. Previous findings showed excellent (Symptom Distress), good

(Interpersonal Relationships) and poor (Social Role) internal consistencies (De Jong et al.,

2008). In this study, the total scale showed excellent internal consistency (α=0.93). Internal

consistency of Symptom Distress was also excellent (α=0.91). Unlike previous findings,

Cronbach’s alpha for Interpersonal Relationships was fair (α=0.75) whereas Social Role

showed inadequate internal consistency (α=0.59).

The Dutch version of the Eating Disorder Examination Questionnaire (EDE-Q; Van Furth,

2000) is a self-report version derived from the Eating Disorder Examination Interview (Fairburn

& Beglin, 1994). It was developed to measure pathological symptoms of eating disorders and

comprises 36 items assessing the frequency of disordered eating attitudes and behaviors in the

past 28 days. The measure contains four subscales: Restraint (‘Have you been deliberately

trying to limit the amount of food you eat to influence your shape or weight?‘), Eating Concern

(‘Has thinking about food, eating or calories made it very difficult to concentrate on things you

are interested in?’), Shape Concern (‘Have you felt fat?‘), and Weight Concern (‘How

dissatisfied have you been with your weight?‘). Higher scores on a 7-point Likert scale (not a

single day, 1-5 days, 6-12 days, 13-15 days, 16-22 days, 23-27 days, and every day) reflect

greater eating-related pathology. This study only used the global score (22 items) of the

measure. The EDE-Q was found to be a valid instrument for assessing pathological symptoms

when using this global score, showing excellent internal consistency (α = 0.95) (Aardoom,

Dingemans, Op ‘t Landt, & Van Furth, 2012). This study also showed excellent internal

consistency of the global score (α=0.90).

The Dutch version of the Severity Indices of Personality Problems, Short Form (SIPP-SF;

Verheul et al., 2008) aims to assess the severity of the generic and changeable components of

personality disorders, i.e. (mal)adaptive personality functioning. It is currently used for research

purposes, especially in outcome research. The instrument comprises 60 items with a 4-point

Likert scale, ranging from 1 (fully disagree) to 4 (fully agree). Respondents’ statements refer to

the past three months. Lower scores reflect less adaptive personality functioning. The five

subscales Self-Control (‘Sometimes I get so overwhelmed that I can’t control my reactions‘),

Identity Integration (‘I am often confused about what kind of person I really am‘),


Responsibility (‘I seem to lack the sense of responsibility necessary to meet my obligations‘),

Relational Capacities (‘It is hard for me to show affection to other people‘), and Social

Concordance (‘It is hard for me to control my aggression towards others‘) contain 12 items each

covering 16 different facets. Unlike the SIPP-118 (long form), psychometric properties of the

SIPP-SF are not available as yet. Internal consistencies of the SIPP-118 were promising with

Cronbach alpha’s ranging from 0.69 to 0.84 with a median of 0.77 for all 16 facets (Verheul et

al., 2008). In this study, good internal consistencies were found for Self Control (α=0.81) and

Responsibility (α=0.81) whereas internal consistency for Relational Capacities was fair

(α=0.75). Social Concordance and Identity Integration showed respectively poor (α=0.67) and

inadequate (α=0.56) Cronbach alpha’s.

Statistical analyses

SPSS Statistics 23 was used to analyse the reliability and validity of the PWB scales and to

explore relations between PWB and maladaptive personality functioning. Demographic

characteristics of the sample were obtained through descriptive statistics and cross tabulations

provided for information on gender and age within the four diagnostic groups. ANOVA tests

and post hoc pairwise comparisons (Tukey) were used to examine differences in age and PWB

subscale scores between the four diagnostic groups.

To test the structure of the PWB scales and explore whether dimensions were able to

account for the correlation between the items, factors were extracted from the 52 items by

means of a principal component analysis in the total sample. The Kaiser-Guttman criterion

(eigenvalues greater than 1.0) and a scree test were used to identify the number of factors. A 6-

factor structure was tested by constraining the number of factors to be extracted to six. To allow

for correlations between the factors, oblimin rotation was applied to interpret the factor

loadings.

Internal consistencies of the six subscales were obtained through Cronbach’s alpha

analyses in the total sample as well as in the four diagnostic groups. Values of 0.90 or higher

were considered as excellent, between 0.80 and 0.89 as good, and between 0.70 and 0.79 as

fair. Values between 0.60 and 0.69 were considered to be poor and below 0.60 to be inadequate

(Cicchetti, 1994).

In accordance with prior findings, convergent validity of the PWB scales with another

measure of well-being and with measures screening and assessing pathological symptoms was

expected. Correlations ≥0.10 but <0.30 were considered as small, correlations ≥0.30 but <0.50

as moderate, and correlations ≥0.50 as strong (Cohen, 1988). Pearson correlation analyses were


conducted to test intercorrelations. The relation between the total scale of PWB and the total

scale of the MHC-SF was expected to be positive and strong as the MHC-SF is another measure

of well-being. With regard to the emotional well-being subscale of the MHC-SF, strong positive

relations were expected for Self-Acceptance, Purpose in Life, and Environmental Mastery,

moderate positive relations for Personal Growth and Positive Relationships with Others and a

weak positive relation for Autonomy (Ryff, 1989). Weak positive relations were expected

between PWB subscales and the social well-being subscale of the MHC-SF (Lamers et al.,

2011). Strong positive relations were expected between PWB subscales and the psychological

well-being subscale of the MHC-SF, considering this subscale was derived from the original

SPWB (Lamers et al., 2011; Ryff, 1989). A moderate negative relation was expected between

the total scale of PWB and the total scale of the OQ-45 as Lamers et al. (2011) found moderate

relations between well-being and psychopathology in the general population. Strong negative

relations were expected between Purpose in Life, Self-Acceptance, and Environmental Mastery

and the subscale Symptom Distress of the OQ-45 as these subscales were found to correlate

more strongly with depression, a key symptom of the subscale Symptom Distress. Moderate

negative relations were expected for the other three PWB subscales and the subscale Symptom

Distress (Ryff, 1989). Furthermore, a strong negative relation was expected between Positive

Relationships with Others and the OQ-45 subscale Interpersonal Relationships considering the

theoretical overlap between the two constructs. A moderate negative relation was expected

between the total scale of PWB and the global score of the EDE-Q. Tomba et al. (2014) found

that PWB dimensions negatively associated with eating disorder behaviour and cognitions,

even when controlling for psychopathological aspects. Hence, the absence of psychological

distress does not simply correspond to the presence of well-being. Moderate negative relations

were expected for most PWB subscales except for Autonomy. The relation for this subscale

was expected to be weak as previous findings found no significant relation (Tomba et al., 2014).

Multivariate linear regression analyses (method forced entry) were performed to

determine which PWB dimensions independently associated with eating pathology (dependent

variable as measured by the EDE-Q). Additionally, a stepwise multivariate linear regression

analysis (method forced entry) was performed to examine whether PWB dimensions explained

eating pathology above and beyond psychopathological symptoms (as measured by the OQ-

45). In the first step, the three domains of psychopathological symptoms were entered. In the

second step, the six dimensions of PWB were entered. Incremental validity was tested through

the change in explained variance in the second step.


Finally, associations between PWB and maladaptive personality functioning were

analysed. Intercorrelations between the subscales of PWB and the subscales of the SIPP-SF

were tested through bivariate analyses followed by interpretation of the correlation coefficients

(Cohen, 1988).

Results

The majority of participants (N=502) were female (98.9%) and aged below 31 (73.6%). The

mean age of the respondents was 27.3 years (standard deviation [SD] = 9.4). Of the respondents,

35.3% (N=177) were diagnosed with AN, 22.7% (N=114) with BN, 12.9% (N=65) with BED,

and 29.1% (N=146) with OSFED (Other Specified Feeding or Eating Disorder). AN-patients

were significantly younger than BN- and BED-patients (respectively M=25.1, SD=8.34,

M=28.4, SD=9.4, and M=31.1, SD=10.4) whereas OSFED-patients (M=27.3, SD=9.3) were

significantly younger than BED-patients. Demographic characteristics per diagnostic group are

shown in Table 2.

Table 3 shows the mean scores on each PWB subscale stratified by the diagnostic

groups. Residuals were normally distributed (Q-Q plots) and equal variances for the four groups

could be assumed (Levene’s tests). One-way ANOVA tests showed significant differences

between groups on the subscale Personal Growth and Self-Acceptance. AN-patients scored

significantly lower than BN-patients on Personal Growth (p=0.042) and Self-Acceptance

(p=0.044).

Information on variation within items as well as means, standard deviations, and

percentile ranks for PWB subscale scores are shown in Appendix B, Tables 1 and 2.

Factorial validity (Exploratory Factor Analysis)

The structure of the Dutch PWB scales was explored by extracting factors from the 52 items by

means of a principal component analysis (PCA) with oblimin rotation. Eleven factors were

extracted based on the Kaiser-Guttman criterion (eigenvalues greater than 1.0), accounting for

59.0% of the total variance (Appendix B, Table 3). The scree plot showed no obvious visual

bend to describe the factors. To test Ryff’s proposed 6-factor structure, another PCA with

oblimin rotation constrained to six factors was applied to the items. The obtained factor

structure partially supported a 6-factor structure of PWB (approximately two-thirds of the items

loaded on the expected factors), as shown in Table 4. Factor 1 (accounting for 24.6% of the

variance) included items mainly coming from Self-Acceptance, but also from Environmental


Mastery, Personal Growth, and Purpose in Life. Factor 2 (6.7% of variance) seemed to

correspond with Ryff’s original Autonomy subscale. Factor 3 (4.8% of variance) included three

items from Personal Growth. Most items that loaded on factor 4 (4.3% of variance) came from

Positive Relationships with Others, only one item came from another subscale. Factor 5 (3.8%

of variance) included items coming from Personal Growth and Purpose in Life. Factor 6 (3.5%

of variance) largely corresponded to Ryff’s subscale Environmental Mastery, although two

items came from Purpose in Life.

Table 2

Demographic characteristics per diagnostic group (N=502)

Variable

ANab

(N=177)

BN

(N=114)

BED

(N=65)

OSFED

(N=146)

Total

Gender, n (%)

Female 174 (98.9) 114 (100) 64 (98.5) 144 (98.6) 496 (99.0)

Male 2 (1.1) - (-) 1 (1.5) 2 (1.4) 5 (1.0)

Age (years), M (SD) 25.1 (8.34) 28.4 (9.4) 31.1 (10.4) 27.3 (9.3) 27.3 (9.4)

16-20, n (%) 71 (40.3) 20 (17.5) 7 (10.8) 35 (24.0) 133 (26.5)

21-30 68 (38.6) 63 (55.3) 28 (43.1) 77 (52.7) 236 (47.1)

31-40 23 (13.1) 17 (14.9) 21 (32.3) 20 (13.7) 81 (16.2)

41-50 11 (6.3) 10 (8.8) 4 (6.2) 7 (4.8) 32 (6.4)

51+ 3 (1.7) 4 (3.5) 5 (7.7) 7 (4.8) 19 (3.8)

Note. a = one missing value in gender; b = one missing value in age; AN=Anorexia Nervosa; BN=Bulimia

Nervosa; BED=Binge Eating Disorder; OSFED=Other Specified Feeding or Eating Disorder; M=Mean;

SD=Standard Deviation.

Table 3

ANOVA differences between PWB subscale scores in diagnostic groups

Variable AN BN BED OSFED p Value*

M(SD) M(SD) M(SD) M(SD)

Purpose In Life 3.91 (0.79)a 3.95 (0.76)a 3.92 (0.80)a 3.94 (0.83)a 0.97

Personal Growth 3.93 (0.65)a 4.15 (0.64)b 4.17 (0.74)a,b 4.11 (0.73)a,b 0.01

Autonomy 2.92 (0.91)a 3.08 (0.84)a 3.20 (0.79)a 3.15 (0.99)a 0.06

Environmental Mastery 3.44 (0.78)a 3.34 (0.82)a 3.33 (0.85)a 3.50 (0.81)a 0.32

Self-Acceptance 2.48 (0.83)a 2.75 (0.82)b 2.76 (0.80)a,b 2.70 (0.92)a,b 0.02

Positive Relationships 3.80 (0.87)a 3.96 (0.83)a 3.96 (0.83)a 3.91 (0.86)a 0.34

Note. * = significance level at 0.05; a,b = means within rows that do not share the same subscript are significantly

different at the 0.05 significance level; AN=Anorexia Nervosa; BN=Bulimia Nervosa; BED=Binge Eating

Disorder; OSFED=Other Specified Feeding or Eating Disorder; M=Mean; SD=Standard Deviation.


Table 4

Exploratory principal component analysis of PWB restricted to six factors

Item Subscale Factor

1 2 3 4 5 6

8 Self-Acceptance 0.68





35 Self Acceptance 0.61


43 Personal Growth 0.58




64 Environmental Mastery 0.44

30 Purpose in Life 0.39




28 Autonomy -0.81

52 Autonomy -0.80

11 Autonomy -0.76

41 Autonomy -0.64

63 Autonomy -0.61

47 Autonomy -0.57

17 Autonomy -0.55

21 Autonomy -0.52


19 Personal Growth 0.51 0.39


10 Positive Relationships -0.76





12 Environmental Mastery -0.63


1 Positive Relationships 0.35 -0.44


(continued on next page)

Eigen values 12.794 3.487 2.488 2.214 1.989 1.810

Note. Item numbers refer to the numbering of the entire PGGS (consisting of 66 items). The table only includes

factor loadings of at least 0.35.


Table 4 (continued)

Exploratory principal component analysis of PWB restricted to six factors

Item Subscale Factor

1 2 3 4 5 6













22 Environmental Mastery -0.38 0.39

Eigen values 12.794 3.487 2.488 2.214 1.989 1.810

Note. Item numbers refer to the numbering of the entire PGGS (consisting of 66 items). The table only includes

factor loadings of at least 0.35.

Internal consistency

Similar Cronbach’s alpha coefficients were found for the total sample and the four diagnostic

groups. Within the total sample, Autonomy, Self-Acceptance and Positive Relationships with

Others showed good internal consistenties (respectively α=0.85, α=0.86, and α=0.82). Internal

consistencies of Personal Growth and Environmental Mastery were fair (respectively α=0.74

and α=0.78). The Cronbach’s alpha coefficient of Purpose in Life was also fair (α=0.77), but

could be slightly improved into 0.79 by deleting item 54. Table 5 shows descriptive statistics

(means, standard deviations, skewness and kurtosis) as well as Cronbach’s alpha coefficients

per diagnostic group.

Convergent validity

Bivariate correlation analyses of the PWB scales with another measure of well-being and

measures assessing psychopathological symptoms and eating pathology are presented in Table

6 (results per diagnostic group are shown in Appendix B, Tables 4-7). In general, correlations

largely corresponded to expectations. As hypothesized, the relation between the total scale of

PWB and the total scale of the MHC-SF was positive and strong. Also in accordance with the

a-priori hypothesis, a strong positive relation was found between Self-Acceptance and the

emotional well-being scale of the MHC-SF. Contrary to expections, only moderate positive


relations were found with Purpose in Life and Environmental Mastery. As expected regarding

the emotional well-being scale of the MHC-SF, moderate positive relations were found with

Personal Growth and Positive Relationships with Others and a weak positive relation with

Autonomy. Most correlations between PWB subscales and the social well-being subscale of the

MHC-SF were positive and moderate which was somewhat stronger than expected. Only

Autonomy showed the expected weak correlation. With regard to the psychological well-being

scale of the MHC-SF, correlations with PWB subscales were positive and strong as expected.

Unlike the a-priori hypothesis, the strength of the correlation with Autonomy was moderate.

The negative relation between the total scale of PWB and the total scale of the OQ-45

was stronger than expected. In accordance with the a-priori hypotheses, strong negative

relations were also found between Purpose in Life, Self-Acceptance, and Environmental

Mastery and the subscale Symptom Distress of the OQ-45. The other three subscales correlated

negatively and moderately with Symptom Distress, as expected. A strong negative relation was

also found between Positive Relationships with Others and Interpersonal Relationships which

was in accordance with expectations.

A moderate negative relation was found between the total scale of PWB and the global

score of the EDE-Q, as expected. In accordance with the a-priori hypotheses, Autonomy and

Self-Acceptance correlated respectively weakly and moderately. The other PWB subscales

showed somewhat weaker correlations than expected.

Table 5

Descriptive statistics and internal consistencies

Variable AN BN BED OSFED

M SD Skew Kurt α α α α α

Purpose In Life 3.93 0.79 -0.17 -0.23 0.77 0.76 0.74 0.79 0.79

Personal Growth 4.06 0.69 -0.20 -0.01 0.74 0.70 0.70 0.77 0.80

Autonomy 3.06 0.91 0.19 -0.46 0.85 0.86 0.81 0.80 0.88

Environmental Mastery 3.42 0.81 -0.21 -0.44 0.78 0.77 0.79 0.80 0.78

Self-Acceptance 2.64 0.86 0.35 -0.28 0.86 0.87 0.84 0.83 0.88

Positive Relationships 3.89 0.85 -0.20 -0.27 0.82 0.84 0.80 0.82 0.82

Note. AN=Anorexia Nervosa; BN=Bulimia Nervosa; BED=Binge Eating Disorder; OSFED=Other Specified

Feeding or Eating Disorder; M=Mean; SD=Standard Deviation; Skew=Skewness; Kurt=Kurtosis; α=Cronbach’s

alpha.


Table 6

Bivariate intercorrelations of PWB subscales and correlations with other measures

Measures

Total

PWB PL PG AUT EM SA PRO

PWB

PL 0.79* -

PG 0.76* 0.61* -

AUT 0.63* 0.29* 0.39* -

EM 0.77* 0.64* 0.42* 0.35* -

SA 0.84* 0.55* 0.57* 0.53* 0.59* -

PRO 0.74* 0.49* 0.49* 0.29* 0.51* 0.51* -

MHC-SF

Emotional well-being 0.57* 0.47* 0.48* 0.25* 0.41* 0.56* 0.38*

Social well-being 0.52* 0.43* 0.37* 0.25* 0.45* 0.44* 0.43*

Psychological well-being 0.67* 0.51* 0.50* 0.37* 0.53* 0.60* 0.50*

Total 0.67* 0.53* 0.51* 0.34* 0.54* 0.61* 0.50*

OQ-45

Symptom Distress -0.66* -0.52* -0.44* -0.36* -0.56* -0.64* -0.45*

Interpersonal Relations -0.61* -0.43* -0.37* -0.30* -0.52* -0.52* -0.61*

Social Role -0.50* -0.39* -0.31* -0.25* -0.54* -0.41* -0.37*

Total -0.69* -0.53* -0.45* -0.36* -0.61* -0.64* -0.53*

EDE-Q

Global score -0.33* -0.25* -0.21* -0.27* -0.22* -0.38* -0.16*

Note. PL=Purpose in Life, PG=Personal Growth, AUT=Autonomy, EM=Environmental Mastery, SA=Self-

Acceptance, PRO=Positive Relationships with Others; MHC-SF=Mental Health Continuum-Short Form;

OQ-45=Outcome Questionnaire 45; EDE-Q=Eating Disorder Examination Questionnaire; * = p<0.001.

Incremental validity

Results of the multivariate regression analyses showed that three out of six PWB dimensions

were independently associated with eating pathology: Purpose in Life (β=-0.13, t=-2.01,

p=0.045), Autonomy (β=-0.11, t=-2.33, p=0.020), and Self-Acceptance (β=-0.35, t=-5.63,

p<0.001). Altogether, PWB dimensions predicted 16.2% of the total variation in eating

pathology (F=15.99, p<0.001).

The stepwise linear regression analysis supported incremental validity as PWB

dimensions explained 3.1% additional variance in eating pathology above and beyond

psychopathological symptoms (ΔF=3.425, p=0.003, adjusted R2 step 2 = 0.25). In the second

step, Autonomy (p=0.017) and Self-Acceptance (p=0.007) remained independently associated

with eating pathology, as shown in Table 7.


Table 7

Stepwise regression analysis explaining variance in eating pathology (EDE-Q) by psychopathological

symptoms (OQ-45) and dimensions of PWB

Eating pathology (EDE-Q)

Model 1 Model 2

Measures Beta t sign Beta t sign

Step 1: OQ-45

Symptom Distress 0.61 10.23 0.00 0.51 7.79 <0.01

Interpersonal Relationships -0.12 -2.16 0.03 -0.11 -1.83 0.07

Social Role -0.09 -1.81 0.07 -0.06 -1.21 0.23

ΔR2 (%) 23.4 (p<0.001) 23.4 (p<0.001)

Step 2: PWB

Purpose in Life -0.06 -0.95 0.35

Personal Growth 0.06 1.08 0.28

Autonomy -0.11 -2.40 0.02

Environmental Mastery 0.11 1.80 0.07

Self-Acceptance -0.17 -2.73 0.01

Positive Relationships 0.05 0.82 0.41

ΔR2 (%) 3.1 (p=0.003)

Note. ΔR2=R square change in explained variance.

Correlations between PWB and maladaptive personality functioning

Bivariate analyses showed that maladaptive personality functioning correlated considerably

with PWB, as shown in Table 8. Within the total sample, all correlations were negative and

significant at the 0.01 level. The SIPP-domains Social Control and Social Concordance

correlated weakly to moderately with PWB subscales which was somewhat weaker than the

correlations found between the other domains and PWB. Identity Integration, Responsibility,

and Relational Capacities correlated mostly moderately with PWB, but strong correlations were

found between the SIPP-domains Identity Integration and Relational Capacities and Self-

Acceptance, between Responsibility and Environmental Mastery, and between Relational

Capacities and Positive Relationships with Others.

In general, correlation patterns within the four diagnostic groups resembled correlations

in the total sample. Nevertheless, not all correlations approached statistical significance (e.g.

within BED-patients). Similar patterns were found within all groups as PWB correlated weakly

to moderately with the SIPP-domains Social Control and Social Concordance and the other

SIPP-domains correlated somewhat stronger with PWB. In addition, Responsibility and

Relational Capacities were strongly associated with respectively Environmental Mastery and

Positive Relationships with Others. Small differences were found between groups. Within AN-

patients and BN-patients, respectively Identity Integration and Relational Capacities correlated


less strong (moderately) with Self-Acceptance than within the other two groups (strongly). On

the other hand, Responsibility was strongly associated with Purpose in Life within BED- and

OSFED-patients, but not within the other two groups.

Table 8

Correlations between PWB and maladaptive personality functioning

PWB dimensions Domains of maladaptive personality functioning

SC II RE RC SCC

All groups (N=502)

Purpose in Life -0.26** -0.39** -0.47** -0.40** -0.20**

Personal Growth -0.24** -0.34** -0.29** -0.35** -0.20**

Autonomy -0.18** -0.36** -0.20** -0.32** -0.08**

Environmental Mastery -0.34** -0.45** -0.55** -0.40** -0.27**

Self-Acceptance -0.27** -0.55** -0.31** -0.50** -0.21**

Positive Relationships with Others -0.31** -0.39** -0.32** -0.60** -0.35**

AN (n=177)

Purpose in Life -0.25** -0.47** -0.48** -0.44** -0.18*

Personal Growth -0.26** -0.33** -0.30** -0.38** -0.21**

Autonomy -0.15 -0.28** -0.16* -0.21** -0.09


Self-Acceptance -0.19* -0.48** -0.28** -0.50** -0.15*


BN (n=114)

Purpose in Life -0.28** -0.38** -0.46** -0.43** -0.22*

Personal Growth -0.36** -0.29** -0.38** -0.24** -0.32**

Autonomy -0.20* -0.40** -0.30** -0.29** -0.06


Self-Acceptance -0.36** -0.58** -0.38** -0.43** -0.24**


BED (n=65)

Purpose in Life -0.21 -0.39** -0.53** -0.43** -0.17

Personal Growth -0.14 -0.33** -0.36** -0.34** -0.04

Autonomy -0.37** -0.48** -0.14 -0.14 -0.04

Environmental Mastery -0.38** -0.45** -0.52** -0.33** -0.24

Self-Acceptance -0.28* -0.53** -0.36** -0.50** -0.23

Positive Relationships with Others -0.32** -0.30* -0.36** -0.56** -0.33**

OSFED (n=146)

Purpose in Life -0.28** -0.32** -0.51** -0.34** -0.22**

Personal Growth -0.20* -0.35** -0.30** -0.37** -0.18*

Autonomy -0.17* -0.35** -0.26** -0.48** -0.07


Self-Acceptance -0.31** -0.59** -0.37** -0.54** -0.26**


Note. SC=Self-Control, II=Identity Integration, RE=Responsibility, RC=Relational Capacities, SCC=Social

Concordance; AN=Anorexia Nervosa, BN=Bulimia Nervosa, BED=Binge Eating Disorder, OSFED=Other

Specified Feeding or Eating Disorder; bold=strong correlation; * = p<0.05; ** = p<0.01.


Discussion

This is the first study that evaluated the Dutch PWB scales within the clinical population of

eating disorder patients. Psychometric properties were examined, including factorial validity,

internal consistency, convergent validity, and incremental validity. The findings suggest that

the construct of PWB can be measured in a fairly reliable and valid way. Support was also

found for incremental validity. In addition, a significant relationship between PWB and

maladaptive personality functioning was revealed suggesting additional value of measuring

both constructs and possible leads for the treatment of patients with comorbid personality

disorders.

The exploratory factor analysis provided for a fair support of Ryff’s 6-factor structure

of PWB as two-third of the items loaded on expected dimensions. In the literature, the factorial

validity of the PWB scales is controversial. A Spanish study which conducted an exploratory

principal component analysis with a similar 9-items per scale version, found less consistency

with Ryff’s structure (Triadó et al., 2007). Some studies supported the 6-factor structure using

confirmatory factor analysis, but only tested the shorter 3-items per scale version (Clarke et al.,

2001; Ryff & Keyes, 1995). Other studies failed to confirm the 6-factor structure for the longer

9- and 14-items per scale versions (Kafka & Kozma, 2002; Springer & Hauser, 2006; Van

Dierendonck, 2004). In this study, some factors contained the expected items whereas other

factors contained items from several dimensions. For example, items from Purpose in Life and

Personal Growth alternately loaded on factor 5. This was in line with the strong correlations

found between these dimensions. Similarly, factor 6 contained items from Purpose in Life and

Environmental Mastery, again showing strong intercorrelations. Besides, Self-Acceptance and

Environmental Mastery correlated quite strongly. Springer & Hauser (2006) reported even

stronger correlations suggesting complete conceptual overlap. The current study, however,

supported the findings by Ryff & Keyes (1995). This means that, although some correlations

were rather strong, the six dimensions appeared to be distinct. As Ryff’s 6-factor structure was

not entirely supported, improvements on the current scales may be needed. However, it should

be taken into account that an exploratory factor analysis is not entirely suitable to either confirm

or refute the factor structure. A confirmative factor analysis would be an appropriate technique

to verify the structure first. For example, a 6-, 4-, and 2-factor structure of PWB could be tested

for the total group and the four diagnostic groups.

The internal consistencies of the six subscales were relatively high showing that items

within dimensions measured the same construct. The coefficients of the current 8/9-items per


scale version ranged from fair to good which is far better than those typically obtained for a 3-

items per scale version (Clarke et al., 2001; Ryff & Keyes, 1995; Van Dierendonck, 2004).

Coefficients were also slightly better than those obtained for similar 9-items per scale versions

(Triadó et al., 2007; Van Dierendonck, 2004). In fact, internal consistencies in this study

resembled those found for the longer 14-items per scale version (Van Dierendonck, 2004).

Similar Cronbach’s alpha coefficients were found within the four diagnostic groups.

Although the findings did not fully support a 6-factor structure, internal consistencies

of the subscales were sufficient. Therefore, it is assumed that the impact on subsequent analyses

performed at a subscale level remained limited. Nevertheless, confirmative factor analysis is

recommended to determine whether the 6-factor structure is plausible.

Support was found for convergent validity as the PWB scales related with other

measures. All correlations were in the expected direction and significant, but some correlation

strengths differed slightly from expectations. With regard to another measure of well-being, for

example, relations between Purpose in Life and Environmental Mastery and the emotional well-

being scale of the MHC-SF were found to be moderate instead of strong. Ryff & Keyes (1995)

reported similar strengths though, stating that correlates were much weaker when happiness

and satisfaction with life was measured by a single item. As the emotional well-being scale of

the MHC-SF only consists of three items, this could explain the current findings. On the other

hand, correlations between PWB subscales and the social well-being scale of the MHC-SF were

somewhat stronger than expected. Possibly, this is due to the fact that Lamers et al. (2011) used

different type of measures for social well-being. As for the psychological well-being scale of

the MHC-SF, Autonomy showed a somewhat weaker relation than expected. This is remarkable

as both the current PWB scales and the psychological well-being scale of the MHC-SF were

derived from the same original PWB scales. However, somewhat weaker correlations were also

found by Ryff (1989).

Relation strengths with a measure for psychopathological symptoms mostly met

expectations. Only the relation between PWB and the total scale of the OQ-45 was stronger

than the moderate correlations reported previously. Possibly, this was due to the use of a

different type of instrument (Lamers et al., 2011). It must also be noted that, so far, the majority

of studies addressed PWB in the general population. For this reason, it cannot be concluded that

PWB is experienced in the same way within clinical populations. Future studies should examine

this into more depth. Alongside the expected moderate to strong relations between PWB and

the OQ-45 subscale Symptom Distress, a strong relation was found between Self Acceptance

and Interpersonal Relations (i.e. interpersonal difficulties resulting from psychopathological


problems). In other words, having a negative attitude towards oneself is very much related to

loneliness or conflicts with other people. Previous findings supported this, showing that self-

acceptance is a prerequisite to have a succesful relationship (Broder, 2013; Ellis, 1986). Also,

Environmental Mastery strongly related to Interpersonal Relations, suggesting that having a

sense of mastery and competence in managing environmental demands plays an important role

in relationships. Strong correlations obtained between Environmental Mastery and Positive

Relationships with Others support this finding. Although both constructs are considered as

essential aspects of mental health (Ryff, 1989), to the knowledge of the author, the relation

between these concepts has not been examined as yet.

Furthermore, relations with a measure assessing eating pathology were significant, but

rather weak. This contradicts previous findings by Tomba et al. (2014) who found mostly

moderate correlations. These differences in strengths may have been caused by the use of

different types of measures. As research on the relation between PWB and eating pathology is

still in a preliminary state, further research is needed to determine the strength of the relation.

Support was found for incremental validity as PWB dimensions explained eating

pathology above and beyond psychopathological symptoms. First, PWB dimensions accounted

for 16.2% of the total variation in eating pathology where Purpose in Life, Autonomy, and Self-

Acceptance were independently associated with eating pathology. Second, PWB dimensions

explained 3.1% additional variance above and beyond psychopathological symptoms where

Autonomy and Self-Acceptance remained independently associated with eating pathology. The

preliminary results of this study are particularly relevant for clinical settings. De Vos et al.

(2017) already found that former patients rated PWB as a key criterion for recovery in addition

to reducing symptoms. The current findings emphasize the value of measuring PWB in addition

to psychopathological symptoms. Also, the findings indicate that patients may benefit from

treatments like Well-Being-Therapy, a recently developed therapy aimed at improving PWB

including self-determinancy/independency and a positive attitude towards oneself

(Christenhusz & Meulenbeek, 2015).

Nevertheless, considering the cross-sectional data of this study, the current findings

should be treated with caution. Data only concern one moment in time (at intake) which restricts

the predictive ability of the scores. Also, PWB scores are likely to become more relevant during

the course of treatment as the absence of mental illness does not imply mental health (Keyes,

2005). Towards the end of the treatment, the incremental validity of the PWB scales may even

increase as pathological symptoms become less. Although this study provides a reason to

measure PWB in addition to psychopathological symptoms, the incremental validity of PWB


during the course of treatment should be examined into more depth by means of a longitudinal

study.

This is the first study that explored the relation between PWB and maladaptive

personality functioning. Multiple significant negative relations were found between the

constructs with minor differences between the four diagnostic groups. As pathology tends to

negatively correlate with PWB, negative correlations are plausible (Keyes, 2005). Three

dimensions of maladaptive personality functioning (i.e. Identity Integration, Responsibility, and

Relational Capacities) correlated considerably with PWB. As Identity Integration includes

aspects like self-reflective functioning and purposefulness (Verheul et al., 2008), it is likely to

measure the same construct as PWB, or at least partially. This seems especially true for Self-

Acceptance showing a strong relation with Identity Integration. It must be noted though that the

internal consistency of Identity Integration was found to be inadequate. This may have

influenced the findings. Responsibility may also have some theoretical overlap with PWB, as

reflected by a strong relation with Environmental Mastery. This is plausible as one can only

take responsibility and be trustworthy when a sense of mastery in managing the demands of the

environment is present. Also, Relational Capacities related considerably with PWB. This

dimension of maladaptive personality functioning includes intimacy, enduring relationships,

and feeling recognized. The found strong correlation with Self-Acceptance is supported by

other findings in this study, showing that the type of attitude towards oneself determines the

quality of relationships. The obtained strong relation with Positive Relationships with Others

can be reasoned as both constructs encompass capabilities like empathy, affection, and

intimacy. Given the fact that these three domains of maladaptive personality functioning

showed (partial) theoretical overlap with PWB, the necessity of measuring them in addition to

PWB is questionable. Relations between PWB and Social Control and Social Concordance

were mostly significant but less strong. The relational strengths obtained for Social Control,

encompassing emotion regulation and effortful control, are supported by Gross & John (2003)

who found similar strengths for emotion regulation. Given the theoretical background of the

construct Social Concordance, encompassing agression regulation, frustration tolerance,

cooperation, and respect, correlations with PWB are also likely to be less strong (Verheul et al.,

2008).

These findings suggest that it may be useful to measure PWB and (domains of)

maladaptive personality functioning in addition to pathological symptoms, in particular with

regard to patients whose long-term treatment outcome is worsened by a comorbid personality

disorder (Martinussen et al., 2017). Although the direction of the relation between PWB and


maladaptive personality functioning is yet unclear, this study also suggests that PWB may

contribute to the alteration of the changeable components of personality functioning (Verheul

et al., 2008). For example, patients with comorbid personality disorders, who score low on PWB

as well as on Social Control and/or Social Concordance, may be offered Well-Being-Therapy

to improve PWB (Christenhusz & Meulenbeek, 2015). Given the found relationship, this may

simultaneously help their personality functioning to become more adaptive. In this way,

positive contributions can be made to the long-term treatment outcome of these patients. The

preliminary findings in this study legitimize further research on the direction and strength of

the relationship between PWB and maladaptive personality functioning.

The current sample contained clearly defined groups and was sufficiently large to

perform analyses for the total group. Significant differences in PWB were found between AN-

and BN-patients, but it should be noted that these sample sizes were rather small. Also, a

comparison between groups would only be valid if the PWB scales measure identical constructs

with the same structure across all groups. Whether patients from all four diagnostic groups

interpret the individual items and underlying contructs in the same way needs further research

though. Such measurement invariance can be examined within the framework of a confirmative

factor analysis by running a set of structural equation models and testing for significant

differences between these models (Van de Schoot, Lugtig, & Hox, 2012).

Altogether, the construct of PWB can be measured in a fairly reliable and valid way by

means of the Dutch PWB scales. However, deployment within the context of routine outcome

monitoring requires further research. First, test-retest reliability needs to be examined to

determine whether the scales measure consistently over time. Second, it is required that the

instrument can measure changes in PWB over time. Although the use of a Likert scale facilitates

the detection of change, it is yet unknown whether effect sizes of differences in scores will be

sufficiently large enough. Finally, it is useful to distinguish between clinical and non-clinical

scores. The development of clinical cut-off scores would enhance the use of the measure within

the context of routinely monitoring treatment outcome.

Some limitations concerning the sample need to be considered. The 1% males in this

study is much lower than the generally assumed prevalence rate of 10% since the 80s. It is also

much lower than recent studies suggested (25-50%) (Cohn, Murray, Walen, & Woolridge,

2016; Vo, Accurso, Goldschmidt, & Le Grange, 2017). Therefore, the current findings cannot

be generalized without reserve to the clinical population of eating disorder patients. Also, the

present sample included patients with comorbid disorders. Comorbidity is common within

eating disorder patients as 56-95% has at least one other diagnosis (Hudson et al., 2007).


However, whilst suffering from other psychopathological symptoms, it cannot be ruled out that

participants’ answers were influenced by such symptoms. This may have had an impact on the

current findings. In addition, as the sample only contained patients with eating disorders as a

first diagnosis whilst leaving out those with a prominent second diagnosis, generalization of the

results to other samples of eating disorder patients with comorbidities is questionable.

There are also some limitations regarding the measures used in this study. First, there

may have been a greater chance of social desirable answers than usual with self-report

questionnaires. Patients with eating disorders and personality disorders were found to be often

displaying deceptive behaviour (Cunnien, 1997) and fast at making judgements on editing

answers (Holtgraves, 2004). Second, besides the PWB scales, the PGGS contained a spiritual

well-being subscale with religious items. Although this subscale was disregarded in the

analyses, the religious items may have influenced the answers on PWB items with regard to

religious participants. It was found that religious priming effects on a number of psychological

outcomes (e.g. prosocial behaviour) generalized to individuals who reported religiosity (Shariff,

Willard, Andersen, & Norenzayan, 2016). Third, the items of the PWB scales were translated

from English into Dutch by means of the forward backward translation procedure. In general,

translation problems were not immediately apparent. However, the backward translation was

not carried out by an independent translator. Besides, this type of procedure may lead to literal

translations, encompassing unnatural wording in the target language, paying less attention to

connotations, naturalness, and comprehensibility. Thus it cannot be ruled out that construct and

item bias may have influenced the psychometric properties (Rode, 2005; Van de Vijver &

Hambleton, 1996; Van der Vijver & Leung, 1997).

The findings of this study showed a reasonable support for the reliability and validity of

the Dutch PWB scales. Nevertheless, further research on the factorial validity is recommended.

Within the framework of a confirmative factor analysis, both the factor structure and invariance

of the measurement between diagnostic groups can be examined. Deployment of the PWB

scales within the context of routine outcome monitoring also requires research on test-retest

reliability and the scales’ capabilities to measure changes over time. Measuring PWB in

addition to psychopathological symptoms appeared to be useful, but incremental validity during

the course of treatment needs to be examined into more depth using longitudinal data. In

addition, further research is recommended on the relationship between PWB and maladaptive

personality functioning considering the possible implications for future treatment of patients

with comorbid personality disorders.


In summary, the Dutch PWB scales provided for a fairly reliable and valid way to

measure the construct of PWB within the clinical population of eating disorder patients. It is

not yet known whether the scales can be used to routinely monitor the patient’s progress during

the course of treatment.


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Appendix A

PWB-items of the PGGS

Item Statement

1 De meeste mensen zien mij als liefdevol en hartelijk.

2 Over het algemeen heb ik het gevoel dat ik grip heb op de situatie waarin ik leef.

3 Ik ben niet geïnteresseerd in activiteiten die mijn horizon zouden kunnen verbreden.

4 Als ik terug kijk op mijn leven dan ben ik tevreden met hoe dingen zijn gelopen.

6 Het handhaven van intieme relaties is moeilijk en frustrerend voor me.

7 Ik leef mijn leven van dag tot dag en ik denk niet echt na over de toekomst.

8 Over het algemeen ben ik positief over mezelf en voel ik me zeker van mezelf.

10 Ik voel me vaak eenzaam omdat ik maar weinig goede vrienden heb waarmee ik mijn zorgen

deel.

11 Mijn beslissingen worden gewoonlijk niet beïnvloed door wat anderen doen.

12 Ik pas niet zo goed bij de mensen en de gemeenschap om mij heen.

13 Ik heb de neiging om me op het heden te richten omdat de toekomst me bijna altijd in de

problemen brengt.

14 Ik heb het gevoel dat veel mensen die ik ken meer uit het leven hebben gehaald dan ik.

16 Ik geniet van persoonlijke gesprekken met familieleden of vrienden.

17 Ik heb de neiging om me zorgen te maken over wat anderen van me denken.

18 Ik ben vrij goed in het hanteren van de vele verantwoordelijkheden in mijn dagelijks leven.

19 Ik heb geen behoefte nieuwe dingen uit te proberen. Mijn leven is prima zoals het is.

21 Gelukkig zijn met mezelf is belangrijker voor me dan de goedkeuring van anderen.

22 Ik voel me vaak overweldigd door mijn verantwoordelijkheden.

23 Ik denk dat het belangrijk is om nieuwe ervaringen te hebben die je uitdagen om over jezelf en

de wereld na te denken.

24 Mijn dagelijkse activiteiten lijken me vaak triviaal en onbelangrijk.

25 Ik houd van de meeste aspecten van mijn persoonlijkheid.

27 Ik heb niet veel mensen om me heen die naar me willen luisteren wanneer ik behoefte heb om

te praten.

28 Ik heb de neiging me te laten beïnvloeden door mensen met een uitgesproken mening.

29 Als ik er over nadenk, dan heb ik mezelf niet echt verbeterd in de loop van de tijd.

30 Ik heb geen duidelijk beeld van wat ik probeer te bereiken in mijn leven.

31 Ik heb fouten gemaakt in het verleden, maar ik heb het gevoel dat alles bij elkaar genomen het

uiteindelijk op zijn pootjes terecht is gekomen.

33 Over het algemeen regel ik mijn persoonlijke financiën en zaken goed.

34 Ik was gewend om doelen te stellen voor mezelf, maar nu lijkt dat alleen maar zonde van de

tijd.

35 Op verschillende vlakken voel ik me teleurgesteld over mijn prestaties in het leven

37 Ik heb het idee dat veel andere mensen meer vrienden hebben dan ik.

38 Ik geniet van het maken van plannen voor de toekomst en het werken eraan om ze

werkelijkheid te laten worden.

40 Mensen zullen me omschrijven als een vrijgevig persoon, bereid om mijn tijd door te brengen

met anderen.

41 Ik heb vertrouwen in mijn opvattingen, zelfs als ze in strijd zijn met de algemene consensus.

42 Ik ben goed in het goochelen met mijn tijd zodat ik alles kan doen wat gedaan moet worden.



(continued)

43 Ik heb het gevoel dat ik me als mens, in de loop van de tijd, goed heb ontwikkeld.

44 Ik ben een actief persoon als het erom gaat de plannen die ik mezelf heb opgelegd uit te

voeren.

46 Ik heb niet veel warme en vertrouwens-waardige relaties met anderen ervaren.

47 Het is moeilijk voor me om mijn opvattingen uit te spreken over tegenstrijdige zaken.

48 Ik vind het niet prettig om in nieuwe situaties te zijn die van me vragen dat ik mijn oude,

vertrouwde manier van dingen doen moet veranderen.

49 Sommige mensen dwalen doelloos door het leven, maar ik ben daar niet een van.

50 Mijn houding over mezelf is waarschijnlijk niet zo positief als hoe de meeste mensen over

zichzelf denken

52 Ik verander vaak van gedachte over beslissingen wanneer mijn vrienden of familie het niet met

me eens zijn.

53 Het leven is voor mij een continu proces van leren, veranderen en groeien.

54 Ik heb soms het gevoel dat ik alles gedaan heb wat er te doen valt in het leven.

56 Ik weet dat ik mijn vrienden kan vertrouwen en zij weten dat ze mij kunnen vertrouwen.

57 Het verleden had zijn pieken en dalen maar over het algemeen zou ik het niet willen

veranderen.

59 Ik heb er moeite mee om mijn leven zo in te richten dat het me voldoening geeft.

60 Ik heb het lang geleden opgegeven om te proberen grote verbeteringen en veranderingen in

mijn leven aan te brengen.

61 Wanneer ik mijzelf vergelijk met vrienden en kennissen dan geeft het me een goed gevoel over

mezelf.

63 Ik beoordeel mezelf op wat ik belangrijk vind, niet op de waarden die anderen belangrijk

vinden.

64 Ik ben erin geslaagd om een thuis en een levensstijl op te bouwen waarbij ik me prettig voel.

65 Er zit een waarheid in het gezegde dat je een oude hond geen nieuwe trucjes kunt leren.


Appendix B

Supplementary results

Table 1

Variation within items (per scale): mean, variance, and item-total correlation

Item M SD rit

Purpose in Life

7 4.42 1.38 0.36

13 4.37 1.20 0.48

24 3.51 1.36 0.48

30 3.25 1.54 0.63

34 3.76 1.28 0.38

38 3.61 1.41 0.58

44 4.01 1.38 0.35

49 3.59 1.40 0.63

54 4.81 1.15 0.11

Personal Growth

3 4.58 1.31 0.44

19 4.69 1.03 0.29

23 4.84 0.94 0.33

29 3.34 1.47 0.45

43 3.37 1.28 0.52

48 2.69 1.28 0.34

53 4.45 1.09 0.48

60 4.14 1.31 0.57

65 4.44 1.05 0.37

Autonomy

11 3.07 1.32 0.65

17 1.80 0.97 0.50

21 3.61 1.53 0.51

28 3.03 1.35 0.71

41 3.50 1.27 0.65

47 3.20 1.28 0.49

52 3.23 1.28 0.65

63 3.03 1.29 0.61


2 3.02 1.29 0.51

12 3.87 1.39 0.39

18 3.90 1.37 0.63

22 2.90 1.28 0.43

33 4.39 1.25 0.36

42 3.56 1.33 0.52

59 2.44 1.07 0.55

64 3.28 1.31 0.48


Note. M=Mean; SD=Standard Deviation; rit=item-total correlation.


Table 1 (continued)

Variation within items (per scale): mean, variance, and item-total correlation

Item M SD rit

Self-Acceptance

4 2.66 1.28 0.63

8 2.24 1.23 0.65

14 2.48 1.38 0.63

25 3.21 1.29 0.63

31 3.23 1.28 0.53

35 2.45 1.20 0.63

50 2.21 1.00 0.45

57 2.91 1.36 0.55

61 2.37 1.08 0.67


1 4.53 1.01 0.36

6 3.19 1.51 0.41

10 3.28 1.53 0.64

16 4.48 1.27 0.44

27 4.16 1.35 0.61

37 2.80 1.48 0.59

40 4.15 1.07 0.47

46 3.98 1.43 0.63

56 4.41 1.17 0.57

Note. M=Mean; SD=Standard Deviation; rit=item-total correlation.


Table 2

Means, standard deviations, and percentile ranks for PWB subscale scores for a sample of Dutch

patients with an eating disorder

Eating disorder population

Total ED AN BN BED OSFED

PWB subscale (N=502) (N=177) (N=114) (N=65) (N=146)

Purpose in Life

M (SD) 3.93 (0.79) 3.91 (0.79) 3.95 (0.76) 3.92 (0.80) 3.94 (0.83)

5 2.67 2.44 2.75 2.59 2.56

10 2.78 2.87 2.89 2.73 2.74

15 3.11 3.22 3.11 2.98 3.01

20 3.22 3.33 3.22 3.33 3.22

30 3.56 3.56 3.44 3.56 3.56

40 3.78 3.78 3.67 3.67 3.78

50 3.89 3.89 3.94 3.89 3.94

60 4.11 4.11 4.22 4.22 4.22

70 4.33 4.22 4.44 4.33 4.44

80 4.56 4.56 4.56 4.64 4.67

85 4.78 4.78 4.86 4.78 4.78

90 5.00 5.00 5.00 4.89 5.00

95 5.22 5.11 5.22 5.34 5.33

100 5.67 5.67 5.44 5.67 5.67

Personal Growth

M (SD) 4.06 (0.69) 3.93 (0.65) 4.15 (0.64) 4.17 (0.74) 4.11 (0.73)

5 2.89 2.77 3.00 3.00 2.78

10 3.11 3.11 3.22 3.11 3.00

15 3.33 3.22 3.44 3.32 3.33

20 3.44 3.33 3.56 3.47 3.49

30 3.67 3.67 3.78 3.67 3.89

40 4.00 3.78 4.00 3.98 4.00

50 4.11 4.00 4.22 4.22 4.22

60 4.22 4.11 4.33 4.33 4.24

70 4.44 4.33 4.56 4.56 4.44

80 4.67 4.44 4.67 4.89 4.67

85 4.78 4.59 4.78 5.01 4.78

90 4.89 4.78 5.00 5.22 5.00

95 5.21 4.89 5.22 5.33 5.29

100 6.00 5.33 5.44 5.67 6.00


Note. ED=eating disorder; AN=Anorexia Nervosa; BN=Bulimia Nervosa; BED=Binge Eating Disorder;

OSFED=Other Specified Feeding or Eating Disorder; M=Mean; SD=Standard Deviation.


Table 2 (continued)






Autonomy

M (SD) 3.06 (0.91) 3.92 (0.91) 3.08 (0.84) 3.20 (0.79) 3.15 (0.99)

5 1.63 1.50 1.75 1.83 1.63

10 1.88 1.63 2.00 2.20 1.88

15 2.13 1.88 2.16 2.25 2.01

20 2.25 2.08 2.25 2.40 2.25

30 2.50 2.38 2.63 2.73 2.63

40 2.75 2.63 2.75 3.00 2.88

50 3.00 3.00 3.06 3.25 3.13

60 3.25 3.13 3.25 3.38 3.38

70 3.50 3.38 3.50 3.65 3.63

80 3.88 3.75 3.75 3.95 4.00

85 4.00 3.88 3.88 4.13 4.25

90 4.38 4.15 4.31 4.30 4.50

95 4.63 4.63 4.75 4.50 5.00

100 5.75 5.00 5.00 4.63 5.75


M (SD) 3.42 (0.81) 3.44 (0.78) 3.33 (0.82) 3.33 (0.85) 3.50 (0.81)

5 2.00 1.99 1.97 1.75 2.00

10 2.29 2.25 2.25 2.00 2.38

15 2.63 2.63 2.50 2.36 2.63

20 2.75 2.75 2.63 2.65 2.75

30 3.00 3.00 2.88 2.75 3.13

40 3.25 3.38 3.13 3.18 3.35

50 3.50 3.50 3.38 3.38 3.50

60 3.63 3.75 3.63 3.50 3.78

70 4.00 4.00 3.94 3.75 4.00

80 4.13 4.13 4.13 4.10 4.13

85 4.25 4.25 4.25 4.26 4.38

90 4.38 4.38 4.25 4.68 4.50

95 4.75 4.51 4.66 4.84 4.83

100 5.38 5.25 5.00 4.88 5.38





Table 2 (continued)






Self-Acceptance

M (SD) 2.64 (0.86) 2.48 (0.83) 2.75 (0.82) 2.76 (0.80) 2.70 (0.92)

5 1.33 1.22 1.53 1.56 1.22

10 1.56 1.44 1.78 1.73 1.52

15 1.67 1.56 1.92 1.88 1.78

20 1.89 1.67 2.00 2.00 1.89

30 2.11 1.89 2.22 2.33 2.12

40 2.33 2.24 2.44 2.44 2.31

50 2.56 2.44 2.67 2.67 2.67

60 2.87 2.56 2.89 3.00 2.89

70 3.11 3.00 3.22 3.11 3.21

80 3.33 3.11 3.44 3.42 3.44

85 3.56 3.37 3.67 3.78 3.66

90 3.86 3.67 3.94 3.89 4.00

95 4.21 3.90 4.22 4.33 4.22

100 5.44 5.44 5.00 4.67 5.22


M (SD) 3.89 (0.85) 3.80 (0.87) 3.96 (0.83) 3.96 (0.83) 3.91 (0.86)

5 2.44 2.33 2.42 2.59 2.26

10 2.78 2.67 2.89 2.91 2.89

15 3.00 2.89 3.03 3.11 3.11

20 3.11 3.00 3.11 3.22 3.22

30 3.44 3.33 3.44 3.33 3.46

40 3.67 3.56 3.78 3.67 3.78

50 3.89 3.78 4.00 3.89 3.89

60 4.11 4.00 4.22 4.11 4.13

70 4.44 4.33 4.56 4.58 4.43

80 4.67 4.56 4.67 4.78 4.67

85 4.78 4.78 4.78 4.89 4.78

90 5.00 4.91 4.94 5.04 5.00

95 5.22 5.23 5.22 5.38 5.22

100 5.89 5.78 5.78 5.67 5.89




Table 3

Principal component analysis with oblimin rotation

Component Eigenvalues Variance (%)

1 12.74 24.60

2 3.49 6.71

3 2.49 4.78

4 2.21 4.26

5 1.99 3.83

6 1.81 3.48

7 1.35 2.59

8 1.29 2.49

9 1.11 2.14

10 1.08 2.08

11 1.04 2.00

12 0.96 1.85

13 0.93 1.80

14 0.89 1.71

15 0.81 1.56

16 0.80 1.54

17 0.80 1.53

18 0.77 1.49

19 0.74 1.42

20 0.72 1.39

21 0.71 1.36

22 0.67 1.30

23 0.65 1.24

24 0.64 1.23

25 0.60 1.14

26 0.58 1.12

27 0.58 1.11

28 0.55 1.05

29 0.52 0.99

30 0.51 0.98

31 0.49 0.95

32 0.48 0.92

33 0.47 0.91

34 0.47 0.90

35 0.45 0.86

36 0.43 0.83

37 0.41 0.79

38 0.39 0.75

39 0.39 0.74

40 0.37 0.72

41 0.36 0.69

42 0.35 0.67

43 0.33 0.64

.. .. ..


Table 4

Bivariate intercorrelations of PWB subscales and correlations with other measures within

AN-patients (N=177)

Measures

Total


PWB

PL 0.75* -

PG 0.71* 0.61* -

AUT 0.59* 0.22 0.27* -

EM 0.77* 0.57* 0.39* 0.34* -

SA 0.80* 0.48* 0.50* 0.49* 0.56* -

PRO 0.71* 0.41* 0.40* 0.22 0.53* 0.44* -

MHC-SF

Emotional well-being 0.52* 0.51* 0.52* 0.14 0.37* 0.48* 0.52*

Social well-being 0.51* 0.38* 0.41* 0.21 0.42* 0.42* 0.51*


Total 0.64* 0.53* 0.52* 0.24* 0.50* 0.55* 0.64*

OQ-45


Interpersonal Relations -0.58* -0.39* -0.39* -0.23 -0.48* -0.44* -0.58*

Social Role -0.47* -0.39* -0.35* -0.16 -0.52* -0.32* -0.47*

Total -0.67* -0.58* -0.46* -0.29* -0.60* -0.54* -0.67*

EDE-Q

Global score -0.37* -0.33* -0.29* -0.32* -0.18 -0.42* -0.07





Table 5


BN-patients (N=114)

Measures

Total


PWB

PL 0.80* -

PG 0.70* 0.51* -

AUT 0.59* 0.26 0.29 -

EM 0.82* 0.73* 0.45* 0.34* -

SA 0.82* 0.54* 0.48* 0.48* 0.67* -

PRO 0.73* 0.54* 0.46* 0.26 0.48* 0.45* -

MHC-SF

Emotional well-being 0.44* 0.27 0.33* 0.22 0.32* 0.53* 0.28



Total 0.65* 0.48* 0.46* 0.34* 0.55* 0.59* 0.48*

OQ-45

Symptom Distress -0.58* -0.39* -0.28 -0.34* -0.56* -0.61* -0.41*

Interpersonal Relations -0.59* -0.41* -0.31 -0.32 -0.49* -0.51* -0.55*

Social Role -0.47* -0.29 -0.23 -0.30 -0.52* -0.44* -0.31

Total -0.63* -0.42* -0.31 -0.36* -0.60* -0.62* -0.48*

EDE-Q

Global score -0.23 -0.08 -0.12 -0.23 -0.15 -0.29 -0.13





Table 6


BED-patients (N=65)

Measures

Total


PWB

PL 0.88* -

PG 0.78* 0.77* -

AUT 0.55* 0.33 0.36 -

EM 0.77* 0.63* 0.39 0.37 -

SA 0.83* 0.64* 0.55* 0.42 0.62* -

PRO 0.68* 0.55* 0.44* 0.09 0.45* 0.47* -

MHC-SF

Emotional well-being 0.67* 0.62* 0.52* 0.25 0.51* 0.64* 0.43*

Social well-being 0.51* 0.42* 0.35 0.25 0.40 0.42* 0.42

Psychological well-being 0.73* 0.64* 0.53* 0.35 0.62* 0.60* 0.53*

Total 0.71* 0.62* 0.52* 0.33 0.58* 0.60* 0.52*

OQ-45

Symptom Distress -0.62* -0.54* -0.39 -0.31 -0.49* -0.66* -0.41

Interpersonal Relations -0.66* -0.51* -0.33 -0.27 -0.63* -0.57* -0.63*

Social Role -0.60* -0.51* -0.32 -0.28 -0.66* -0.51* -0.39

Total -0.71* -0.59* -0.41 -0.33 -0.63* -0.69* -0.52*

EDE-Q

Global score -0.27 -0.18 -0.19 -0.24 -0.15 -0.25 -0.21





Table 7


OSFED-patients (N=146)

Measures

Total


PWB

PL 0.79* -

PG 0.82* 0.62* -

AUT 0.72* 0.36* 0.56* -

EM 0.76* 0.66* 0.48* 0.39* -

SA 0.88* 0.60* 0.68* 0.61* 0.61* -

PRO 0.80* 0.53* 0.60* 0.45* 0.55* 0.65* -

MHC-SF

Emotional well-being 0.64* 0.49* 0.50* 0.37* 0.52* 0.62* 0.53*



Total 0.70* 0.55* 0.52* 0.43* 0.57* 0.68* 0.59*

OQ-45


Interpersonal Relations -0.65* -0.45* -0.41* -0.36* -0.53* -0.60* -0.72*

Social Role -0.53* -0.41* -0.34* -0.33* -0.53* -0.48* -0.45*

Total -0.75* -0.54* -0.54* -0.44* -0.65* -0.74* -0.67*

EDE-Q

Global score -0.43* -0.30* -0.27 -0.32* -0.33* -0.52* -0.30*




Documents

Psychological well-being within eating disorder patientsessay.utwente.nl/74827/1/Fenne van Holthe_MA_BMS.pdfPsychological well-being within eating disorder patients Validation of the